1. Field of the Invention
The present invention relates to an ink image receiving sheet usable in thermal ink-transfer recording which is to be used in such a manner that a thermal ink-transfer recording medium (ink donor sheet) comprising a heat-meltable or heat-sublimable ink coated on one side of a support made of a paper, a plastic film or the like is laminated on the ink image receiving sheet and the recording medium is selectively heated according to image information to transfer the ink, which is molten or sublimed by heat, onto the ink image receiving sheet, thereby recording the image information.
2. Prior Art
It has been thought that no special sheets are necessary for the heat transfer recording and that ordinal plain papers for printing are sufficient for this purpose. Under these circumstances, those skilled in the art have been scarcely interested in such sheets.
However, as the recording speed of the heat transfer recording system is increased, the image resolution and ink-transfer efficiency are reduced disadvantageously. To overcome these defects, processes for improving the ink donor sheets and for improving the apparatus have been proposed
For example, for preventing the reduction of the image resolution or ink-transfer efficiency, a process wherein an inorganic pigment having a high oil absorption is incorporated in the ink image receiving sheet [see Japanese Patent Unexamined Published Application (hereinafter referred to as `J. P. KOKAI`) No.63-19289] and a process wherein a porous coating layer having a high oil absorption is formed on the ink image receiving sheet (see J. P. KOKAI No.62-160286) were proposed.
However, even by these processes, a sufficient image resolution or ink-transfer efficiency cannot be always obtained.